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Das D, Mattaparthi VSK. Computational investigation on the conformational dynamics of C-terminal truncated α-synuclein bound to membrane. J Biomol Struct Dyn 2024:1-13. [PMID: 38321955 DOI: 10.1080/07391102.2024.2310788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 01/22/2024] [Indexed: 02/08/2024]
Abstract
Accelerated progression rates in Parkinson's disease (PD) have been linked to C-terminal domain (CTD) truncations of monomeric α-Synuclein (α-Syn), which have been suggested to increase amyloid aggregation in vivo and in vitro. In the brain of PD patients, CTD truncated α-Syn was found to have lower cell viability and tends to increase in the formation of fibrils. The CTD of α-Syn acts as a guard for regulating the normal functioning of α-Syn. The absence of the CTD may allow the N-terminal of α-Syn to interact with the membrane thereby affecting the normal functioning of α-Syn, and all of which will affect the etiology of PD. In this study, the conformational dynamics of CTD truncated α-Syn (1-99 and 1-108) monomers and their effect on the protein-membrane interactions were demonstrated using the all-atom molecular dynamics (MD) simulation method. From the MD analyses, it was noticed that among the two truncated monomers, α-Syn (1-108) was found to be more stable, shows rigidness at the N-terminal region and contains a significant number of intermolecular hydrogen bonds between the non-amyloid β-component (NAC) region and membrane, and lesser number of extended strands. Further, the bending angle in the N-terminal domain was found to be lesser in the α-Syn (1-108) in comparison with the α-Syn (1-99). Our findings suggest that the truncation on the CTD of α-Syn affects its interaction with the membrane and subsequently has an impact on the aggregation.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Dorothy Das
- Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
| | - Venkata Satish Kumar Mattaparthi
- Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
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Sharma B, Mattaparthi VSK. Prediction of interface between regions of varying degrees of order or disorderness in intrinsically disordered proteins from dihedral angles. J Biomol Struct Dyn 2023:1-11. [PMID: 38116756 DOI: 10.1080/07391102.2023.2294837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 12/06/2023] [Indexed: 12/21/2023]
Abstract
Intrinsically disordered proteins (IDPs) are proteins that do not form uniquely defined three-dimensional (3-D) structures. Experimental research on IDPs is difficult since they go against the traditional protein structure-function paradigm. Although there are several predictors of disorder based on amino acid sequences, but very limited based on the 3-D structures of proteins. Dihedral angles have a significant role in predicting protein structure because they establish a protein's backbone, which, coupled with its side chain, establishes its overall shape. Here, we have carried out atomistic Molecular Dynamics (MD) simulations on four different proteins: one ordered protein (Monellin), two partially disordered proteins (p53-TAD and Amyloid beta (Aβ1-42) peptide), and one completely disordered protein (Histatin 5). The MD simulation trajectories for the corresponding four proteins were used to conduct dihedral angle (ϕ and ѱ) analysis. Then, the average dihedral angles for each of the residues were calculated and plotted against the residue index. We noticed steep rises or falls in the average ϕ value at certain locations in the plot. These sudden shifts in the average ϕ value reflect the interface between regions of varying degrees of order or disorderness in intrinsically disordered proteins. Using this method, the probable conformer of a protein with a higher degree of disorder can be found among the ensembles of structures sampled during the MD simulations. The results of our study offer new understandings on precisely identifying regions of various degrees of disorder in intrinsically disordered proteins.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Babli Sharma
- Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Assam, India
| | - Venkata Satish Kumar Mattaparthi
- Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Assam, India
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Das D, Bharadwaz P, Mattaparthi VSK. Computational investigation on the effect of the peptidomimetic inhibitors (NPT100-18A and NPT200-11) on the α-synuclein and lipid membrane interactions. J Biomol Struct Dyn 2023:1-12. [PMID: 37768058 DOI: 10.1080/07391102.2023.2262599] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 09/18/2023] [Indexed: 09/29/2023]
Abstract
Parkinson's disease (PD) is associated with α-synuclein (α-Syn), a presynaptic protein that binds to cell membranes. The molecular pathophysiology of PD most likely begins with the binding of α-Syn to membranes. Recently, two peptidomimetic inhibitors (NPT100-18A and NPT200-11) were identified to potentially interact with α-Syn and affect the interaction of α-Syn with the membrane. In this study, the effect of the two peptidomimetic inhibitors on the α-Syn-membrane interaction was demonstrated. DFT calculations were performed for optimization of the two inhibitors, and the nucleophilicity (N) and electrophilicity (ω) of NPT100-18A and NPT200-11 were calculated to be 3.90 and 3.86 (N); 1.06 and 1.04 (ω), respectively. Using the docking tool (CB-dock2), the two α-Syn-peptidomimetic inhibitor complexes (α-Syn-NPT100-18A and α-Syn-NPT200-11) have been prepared. Then all-atom molecular dynamics (MD) simulation was carried out on the α-Syn (control), α-Syn-NPT100-18A and α-Syn-NPT200-11 complex systems in presence of DOPE: DOPS: DOPC (5:3:2) lipid bilayer. From the conformational dynamics analysis, the 3-D structure of α-Syn was found to be stable, and the helices present in the regions (1-37) and (45-95) of α-Syn were found to be retained in the presence of the two peptidomimetic inhibitors. The electron density profile analysis revealed the binding modes of NAC and C-terminal region of α-Syn (in the presence of NPT200-11 inhibitor) with lipid membrane are in the close vicinity from the lipid bilayer centre. Our findings in this study on α-Syn-membrane interactions may be useful for developing a new therapeutic approach for treating PD and other neurodegenerative disorders.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Dorothy Das
- Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
| | - Priyam Bharadwaz
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Prague, Czech Republic
| | - Venkata Satish Kumar Mattaparthi
- Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
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Carnazza KE, Komer LE, Xie YX, Pineda A, Briano JA, Gao V, Na Y, Ramlall T, Buchman VL, Eliezer D, Sharma M, Burré J. Synaptic vesicle binding of α-synuclein is modulated by β- and γ-synucleins. Cell Rep 2022; 39:110675. [PMID: 35417693 PMCID: PMC9116446 DOI: 10.1016/j.celrep.2022.110675] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 01/23/2022] [Accepted: 03/22/2022] [Indexed: 12/16/2022] Open
Abstract
α-synuclein, β-synuclein, and γ-synuclein are abundantly expressed proteins in the vertebrate nervous system. α-synuclein functions in neurotransmitter release by binding to and clustering synaptic vesicles and chaperoning SNARE-complex assembly. Pathologically, aggregates originating from soluble pools of α-synuclein are deposited into Lewy bodies in Parkinson's disease and related synucleinopathies. The functions of β-synuclein and γ-synuclein in presynaptic terminals remain poorly studied. Using in vitro liposome binding studies, circular dichroism spectroscopy, immunoprecipitation, and fluorescence resonance energy transfer (FRET) experiments on isolated synaptic vesicles in combination with subcellular fractionation of brains from synuclein mouse models, we show that β-synuclein and γ-synuclein have a reduced affinity toward synaptic vesicles compared with α-synuclein, and that heteromerization of β-synuclein or γ-synuclein with α-synuclein results in reduced synaptic vesicle binding of α-synuclein in a concentration-dependent manner. Our data suggest that β-synuclein and γ-synuclein are modulators of synaptic vesicle binding of α-synuclein and thereby reduce α-synuclein's physiological activity at the neuronal synapse.
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Affiliation(s)
- Kathryn E Carnazza
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Lauren E Komer
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Ying Xue Xie
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - André Pineda
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Juan Antonio Briano
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Virginia Gao
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Yoonmi Na
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Trudy Ramlall
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10021, USA
| | - Vladimir L Buchman
- School of Biosciences, Cardiff University, Cardiff CF103AX, UK; Belgorod State National Research University, 85 Pobedy Street, Belgorod, Belgorod 308015, Russian Federation
| | - David Eliezer
- Department of Biochemistry, Weill Cornell Medicine, New York, NY 10021, USA
| | - Manu Sharma
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA
| | - Jacqueline Burré
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10021, USA.
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NMR unveils an N-terminal interaction interface on acetylated-α-synuclein monomers for recruitment to fibrils. Proc Natl Acad Sci U S A 2021; 118:2017452118. [PMID: 33903234 DOI: 10.1073/pnas.2017452118] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Amyloid fibril formation of α-synuclein (αS) is associated with multiple neurodegenerative diseases, including Parkinson's disease (PD). Growing evidence suggests that progression of PD is linked to cell-to-cell propagation of αS fibrils, which leads to seeding of endogenous intrinsically disordered monomer via templated elongation and secondary nucleation. A molecular understanding of the seeding mechanism and driving interactions is crucial to inhibit progression of amyloid formation. Here, using relaxation-based solution NMR experiments designed to probe large complexes, we probe weak interactions of intrinsically disordered acetylated-αS (Ac-αS) monomers with seeding-competent Ac-αS fibrils and seeding-incompetent off-pathway oligomers to identify Ac-αS monomer residues at the binding interface. Under conditions that favor fibril elongation, we determine that the first 11 N-terminal residues on the monomer form a common binding site for both fibrils and off-pathway oligomers. Additionally, the presence of off-pathway oligomers within a fibril seeding environment suppresses seeded amyloid formation, as observed through thioflavin-T fluorescence experiments. This highlights that off-pathway αS oligomers can act as an auto-inhibitor against αS fibril elongation. Based on these data taken together with previous results, we propose a model in which Ac-αS monomer recruitment to the fibril is driven by interactions between the intrinsically disordered monomer N terminus and the intrinsically disordered flanking regions (IDR) on the fibril surface. We suggest that this monomer recruitment may play a role in the elongation of amyloid fibrils and highlight the potential of the IDRs of the fibril as important therapeutic targets against seeded amyloid formation.
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Ivanova MI, Lin Y, Lee YH, Zheng J, Ramamoorthy A. Biophysical processes underlying cross-seeding in amyloid aggregation and implications in amyloid pathology. Biophys Chem 2020; 269:106507. [PMID: 33254009 DOI: 10.1016/j.bpc.2020.106507] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 11/13/2020] [Accepted: 11/13/2020] [Indexed: 12/18/2022]
Abstract
Abnormal aggregation of proteins into filamentous aggregates commonly associates with many diseases, such as Alzheimer's disease, Parkinson's disease and type-2 diabetes. These filamentous aggregates, also known as amyloids, can propagate their abnormal structures to either the same precursor molecules (seeding) or other protein monomers (cross-seeding). Cross-seeding has been implicated in the abnormal protein aggregation and has been found to facilitate the formation of physiological amyloids. It has risen to be an exciting area of research with a high volume of published reports. In this review article, we focus on the biophysical processes underlying the cross-seeding for some of the most commonly studied amyloid proteins. Here we will discuss the relevant literature related to cross-seeded polymerization of amyloid-beta, human islet amyloid polypeptide (hIAPP, or also known as amylin) and alpha-synuclein. SEVI (semen-derived enhancer of viral infection) amyloid formation by the cross-seeding between the bacterial curli protein and PAP248-286 is also briefly discussed.
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Affiliation(s)
- Magdalena I Ivanova
- Neurology, University of Michigan, Ann Arbor, MI 48109, USA; Biophysics, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Yuxi Lin
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute, Ochang, Chungbuk 28119, South Korea
| | - Young-Ho Lee
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute, Ochang, Chungbuk 28119, South Korea; Bio-Analytical Science, University of Science and Technology, Daejeon 34113, South Korea; Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon 34134, South Korea; Research headquarters, Korea Brain Research Institute, Daegu 41068, South Korea
| | - Jie Zheng
- Department of Chemical and Biomolecular Engineering, The University of Akron, Ohio, USA
| | - Ayyalusamy Ramamoorthy
- Biophysics, University of Michigan, Ann Arbor, MI 48109, USA; Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA; Macromolecular Science and Engineering, University of Michigan, Ann Arbor, MI 48109, USA; Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA.
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Borah P, Sanjeev A, Mattaparthi VSK. Computational investigation on the effect of Oleuropein aglycone on the α-synuclein aggregation. J Biomol Struct Dyn 2020; 39:1259-1270. [PMID: 32041489 DOI: 10.1080/07391102.2020.1728384] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Parkinson's disease (PD) is considered to be the second most common progressive neurodegenerative brain disorder after Alzheimer's disease, which is caused by misfolding and aggregation of Alpha-synuclein (α-synuclein). It is characterized by distinct aggregated fibrillary form of α-synuclein known as the Lewy bodies and Lewy neurites. The most promising approach to combat PD is to prevent the misfolding and subsequent aggregation of α-synuclein. Recently, Oleuropein aglycone (OleA) has been reported to stabilize the monomeric structure of α-synuclein, subsequently favoring the growth of nontoxic aggregates. Therefore, understanding the conformational dynamics of α-synuclein monomer in the presence of OleA is significant. Here, we have investigated the effect of OleA on the conformational dynamics and the aggregation propensity of α-synuclein using molecular dynamics simulation. From molecular dynamics trajectory analysis, we noticed that when OleA is bound to α-synuclein, the intramolecular distance between non-amyloid-β component domain and C-terminal domain of α-synuclein was increased, whereas long-range hydrophobic interactions between the two region were reduced. Oleuropein aglycone was found to interact with the N-terminal domain of α-synuclein, making this region unavailable for interaction with membranes and lipids for the formation of cellular toxic aggregates. From the binding-free energy analysis, we found binding affinity between α-synuclein and OleA to be indeed high (ΔGbind = -12.56 kcal mol-1 from MM-PBSA and ΔGbind = -27.41 kcal mol-1from MM-GBSA). Our findings in this study thus substantiate the effect of OleA on the structure and stabilization of α-synuclein monomer that subsequently favors the growth of stable and nontoxic aggregates.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Priyanka Borah
- Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
| | - Airy Sanjeev
- Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
| | - Venkata Satish Kumar Mattaparthi
- Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
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Wang L, Zheng G, Liu X, Ni D, He X, Cheng J, Lu S. Molecular dynamics simulations provide insights into the origin of gleevec's selectivity toward human tyrosine kinases. J Biomol Struct Dyn 2018; 37:2733-2744. [PMID: 30052122 DOI: 10.1080/07391102.2018.1496139] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Protein kinases are critical drug targets against cancer. Since the discovery of Gleevec, a specific inhibitor of Abl kinase, the capability of this drug to distinguish between Abl and other tyrosine kinases, such as Src, has been intensely investigated but the origin of Gleevec's selectivity to Abl against Src is less studied. Here, we performed molecular dynamics (MD) simulations, dynamical cross-correlation matrices (DCCM), dynamical network analysis, and binding free energy calculations to explore Gleevec's selectivity based on the crystal structures of Abl, Src, and their common ancestors (ANC-AS) and the two constructed mutation systems (AS→Abl and AS→Src). MD simulations revealed that the conformation of the phosphate-binding loop (P-loop) was altered significantly in the AS→Abl system. DCCM results unraveled that mutations increased anticorrelated motions in the AS→Abl system. Community network analysis suggested that the P-loop established special contacts in the AS→Abl system that are devoid in the AS→Src system. The binding free energy calculations unveiled that the affinity of Gleevec to AS→Abl increased to near the Abl level, whereas its affinity to AS→Src decreased to near the Src level. Analysis of individual residue contributions showed that the differences were located mainly at the P-loop. This study is valuable for understanding the sensitivity of Gleevec to human tyrosine kinases. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Lulu Wang
- a Department of Critical Care Medicine , Binzhou Medical University Hospital , Binzhou , Shandong , China
| | - Guodong Zheng
- b Department of VIP clinic , Changhai Hospital, Naval Military Medical University , Shanghai , China
| | - Xianxian Liu
- c Department of Infectious Diseases , Binzhou Medical University Hospital , Binzhou , Shandong , China
| | - Duan Ni
- d Department of Pathophysiology Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education , Shanghai Jiao Tong University, School of Medicine , Shanghai , China
| | - Xinheng He
- d Department of Pathophysiology Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education , Shanghai Jiao Tong University, School of Medicine , Shanghai , China
| | - Jinying Cheng
- c Department of Infectious Diseases , Binzhou Medical University Hospital , Binzhou , Shandong , China
| | - Shaoyong Lu
- d Department of Pathophysiology Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education , Shanghai Jiao Tong University, School of Medicine , Shanghai , China
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Williams JK, Yang X, Baum J. Interactions between the Intrinsically Disordered Proteins β-Synuclein and α-Synuclein. Proteomics 2018; 18:e1800109. [PMID: 30142698 PMCID: PMC6447293 DOI: 10.1002/pmic.201800109] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 08/18/2018] [Indexed: 12/31/2022]
Abstract
Several intrinsically disordered proteins have been implicated in the process of amyloid fibril formation in neurodegenerative disease, and developing approaches to inhibit the aggregation of these intrinsically disordered proteins is critical for establishing effective therapies against disease progression. The aggregation pathway of the intrinsically disordered protein alpha-synuclein, which is implicated in several neurodegenerative diseases known as synucleinopathies, has been extensively characterized. Less attention has been leveraged on beta-synuclein, a homologous intrinsically disordered protein that co-localizes with alpha-synuclein and is known to delay alpha-synuclein fibril formation. In this review, we focus on beta-synuclein and the molecular-level interactions between alpha-synuclein and beta-synuclein that underlie the delay of fibril formation. We highlight studies that begin to define alpha-synuclein and beta-synuclein interactions at the monomer, oligomer, and surface levels, and suggest that beta-synuclein plays a role in regulation of inhibition at many different stages of alpha-synuclein aggregation.
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Affiliation(s)
- Jonathan K Williams
- Department of Chemistry and Chemical Biology, Rutgers University, 08854, Piscataway, New Jersey, USA
| | - Xue Yang
- Department of Chemistry and Chemical Biology, Rutgers University, 08854, Piscataway, New Jersey, USA
| | - Jean Baum
- Department of Chemistry and Chemical Biology, Rutgers University, 08854, Piscataway, New Jersey, USA
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Sanjeev A, Mattaparthi VSK. Computational investigation on the effects of H50Q and G51D mutations on the α-Synuclein aggregation propensity. J Biomol Struct Dyn 2017. [PMID: 28650719 DOI: 10.1080/07391102.2017.1347060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The aggregation of α-synuclein is linked directly to the histopathology of Parkinson's disease (PD). However, several missense mutations present in the α-synuclein gene (SNCA) have been known to be associated with PD. Several studies have highlighted the effect of SNCA mutations on the α-synuclein aggregation, but their pathological roles are not completely established. In this study, we have focused on the effects of the recently discovered α-synuclein missense mutants (H50Q and G51D) on the aggregation using computational approaches. We performed all atom molecular dynamics (MD) simulation on these mutants and compared their conformational dynamics with Wild-Type (WT) α-synuclein. We noticed the solvent accessible surface area (SASA), radius of gyration, atomic fluctuations, and beta strand content to be higher in H50Q than G51D and WT. Using PDBSum online server; we analyzed the inter-molecular interactions that drive the association of monomeric units of H50Q, WT, and G51D in forming the respective homo-dimer. We noticed the interface area, number of interacting residues and binding free energy to be higher for H50Q homo-dimer than the WT and G51D homo-dimers. Our findings in this study suggest that in comparison to WT and G51D, H50Q mutation to have a positive effect on increasing the α-synuclein aggregation propensity. Hence, we see that H50Q and G51D mutation show conflicting effect on the aggregation propensity of α-synuclein.
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Affiliation(s)
- Airy Sanjeev
- a Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology , Tezpur University , Tezpur , Assam 784 028 , India
| | - Venkata Satish Kumar Mattaparthi
- a Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology , Tezpur University , Tezpur , Assam 784 028 , India
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